How to align objects to the center of another object
The way to solve this is pretty simple: Select the objects you want to align, go to the "object" tab, and select "transform". This will give you another drop down menu, which at the bottom of is the option "Align objects". Select this, and a menu will appear on the left. It will show some options for aligning the selected objects. Play around with these settings until you have a pleasing result. You can also shift-click on the x,y,z align options to align on multiple axes at the same time.